For the samosas: Preheat the oven to 375 degrees F. Line 2 baking sheets with parchment paper.
Heat the oil in a medium saute pan over medium-high heat until shimmering, about 2 minutes. Add the onions
and chiles and season with salt and pepper. Cook until golden and fragrant, 4 to 5 minutes. Fold into the mashed potatoes, peas
and coconut and set aside.
Cut the empanada discs in half. Take a half circle of dough and dampen the cut edge lightly with water, overlapping the cut edge with itself and sealing to making a cone. Fill the cone with 2 tablespoons filling. Dampen the open edge lightly with water and overlap the edges to seal shut. Repeat with the remaining dough
Set the samosas on the prepared baking sheet and bake until golden brown at the corners and a bit bubbly looking, about 25 minutes, rotating halfway.
For the raita: Season the cucumber with 1 teaspoon salt and let drain
in a mesh strainer
or on some paper towels for about 10 minutes. Squeeze out the excess liquid. Fold the cucumber, yogurt, ginger
and cayenne together. Serve with the samosas.